Project Summary Simulation training is unique in its ability for repetitive practice of a wide variety of scenarios and to reflect on performance without jeopardizing a patient?s safety. Surgical skills simulators have been successful in bridging gaps of the current training model; however, these simulators fall short of offering a complete operative experience. Operative exposure with live patients still remains the vanguard of hands-on clinical training. Under supervision and guidance, training surgeons inherently practice and refine skills on patients during residency, exposing them to unnecessary risks. Novel simulation tools are needed to both validate and implement novel surgical techniques, including those for minimally invasive cranial neurosurgery. To enhance the efficiency, safety and comprehensiveness of minimally invasive surgical training, we propose to develop an inanimate cranial neurosurgery model utilizing novel concepts in 3D printing technology. We have engineered a model to simulate evacuation of a blood clot from the brain, and we propose to modify this model to simulate resection of a brain tumor. Through this model, comprehensive procedural training and competence can be achieved prior to operative exposure. We plan to validate this models by comparing several clinical metrics in experienced surgeons and trainees. We will also validate the physical realism of this model by testing the mechanical and imaging properties relative to human tissue.